The Rangers committed nearly $108 million for Darvish, winning the posting bid at $51.7 million before signing him to a six-year, $56 million contract. With the new posting system that restricts the release fee to $20 million, Tanaka should easily surpass Darvish’s contract.

Thanks to the success of Darvish, other NPB pitchers and growing industry revenues, the total package a team pays to secure Tanaka—posting fee and contract combined—could also surpass what the Rangers paid for Darvish.

Will Tanaka be as electric against MLB hitters as Darvish has been in his first two years? After watching several of Tanaka’s starts this season and speaking with scouts about him, here’s a tale of the tape between Darvish and Tanaka at the time both of them left Japan.

PERFORMANCE

Tanaka had more immediate success coming out of high school than Darvish. As an 18-year-old, Tanaka stepped into the Rakuten Eagles’ starting rotation and struck out 196 batters in 186 1/3 innings with a 3.82 ERA. When Darvish was 18, he did have a lower ERA (3.53) but his 52-48 K-BB mark in 94 1/3 innings was less impressive.

But Darvish and Tanaka both quickly became stars in Japan. As a 20-year-old in 2007, Darvish won the Sawamura Award, Japan’s equivalent of the Cy Young. Tanaka won two Sawamura Awards, one in 2011 (Darvish’s final season in Japan) and another in 2013.

In their final respective Japanese seasons, Tanaka (1.27) had Darvish (1.44) slightly beat in ERA. The difference becomes more pronounced when accounting for the change in run environment in the Pacific League, where in 2011 the league average ERA was 2.95, then jumped to 3.57 in 2013. In terms of run prevention, Tanaka gets a small edge.

Both pitchers averaged 1.4 walks per nine innings in their final season in Japan, but the difference maker is Darvish’s ability to miss bats. Tanaka has swing-and-miss stuff, ranking second in the Pacific League in strikeouts last year (183 in 212 innings) and averaging 7.8 K/9. Darvish’s whiff rate in 2011 was even more prolific, with 276 strikeouts in 232 innings for an average of 10.7 K/9, an edge that jumps out to analysts in major league front offices. This one could go either way.

Advantage: EVEN

FASTBALL

Darvish left Japan with a fastball that sat at 92-95 mph and had touched 99 in relief, and with the Rangers he’s generally been around the same range. Tanaka parks around 89-94 mph and can hit 96 with his four-seam fastball when he needs a little extra gas. Both pitchers throw different variations of their fastball, mixing four-seam, two-seam and cutter grips for different effect. Darvish throws harder than Tanaka, has a little extra life on his fastball and gets better downhill angle on the pitch.

Advantage: DARVISH

SLIDER

Tanaka has a plus slider that grades out even better at times, though there were also starts last season when the pitch got away from him and lacked its usual two-plane tilt. At its best, Tanaka’s slider is a swing-and-miss pitch at 82-85 mph, diving hard and away from righthanded hitters. When he gets in trouble it’s often because he leaves it up in the zone, a mistake he can get away with more in Japan than against major league hitters.

While Tanaka’s slider is an out pitch, Darvish’s slider is one of the nastiest pitches in baseball. In Baseball America’s annual Best Tools survey, American League managers voted Darvish as having the third-best slider in the AL in 2012 and 2013, behind Chris Sale and Max Scherzer last season. It’s a 70 on the 20-80 scale and a pitch Darvish uses frequently.

Advantage: DARVISH

SPLITTER

This one is no contest. Darvish throws an occasional hard splitter around 87-90 mph, but it’s not a major part of his repertoire. For Tanaka, it’s the pitch that makes him dangerous. It comes out of his hand looking like a fastball at the belt, then has late movement after the point of decision for the hitter, falling off the table and tumbling below the hitter’s knees.

In the past Tanaka had leaned more on his slider, but his splitter (and his command of the pitch) improved so much this season that it’s become a more essential component in his arsenal. It’s a devastating pitch—“like John Smoltz” in the words of one National League scout—that earns plus-plus marks from scouts.

Advantage: TANAKA

CURVEBALL

Tanaka leans primarily on his fastball, splitter and slider, but he will sprinkle in a curveball as well to show hitters another speed. It’s a slow bender, usually in the low-70s but occasionally a little harder. He uses the curveball early in the count as a get-me-over pitch, but when he gets to a two-strike count he’ll go to the fastball, split or slider for his finishing pitch.

Darvish leans mostly on his fastball and slider, but his curveball is surprisingly effective. He adds and subtracts from his curve, throwing it as slow as the low-60s. He’ll throw his slow, rainbow curveball even with two strikes, getting swings and misses that make hitters look as foolish against the pitch as anything else he throws, when used judiciously.

Advantage: DARVISH

COMMAND/CONTROL

In his final season in Japan, Darvish walked 4.1 percent of batters he faced. Last season Tanaka walked 3.9 percent of batters. So they were about equal at preventing walks in their final seasons in Japan. But Tanaka has a longer track record of throwing strikes. In Darvish’s previous two seasons (2009-10), he walked 6.1 percent of batters; in Tanaka’s previous two seasons (2011-12), he walked just 2.9 percent of batters.

In Darvish’s rookie year with the Rangers, he walked 4.2 batters per nine innings, or 10.9 percent of batters he faced. While Darvish came over with stronger reports on his control than his rookie numbers would indicate, Tanaka should be able to maintain a lower walk rate next season.

“He’s going to throw strikes,” said an American League scout. “He’s going to be around the plate, and he can command his pitches off the strike zone as well.”

Advantage: TANAKA

DELIVERY/PHYSICAL

Darvish and Tanaka are both good athletes who are able to repeat their deliveries with good balance and coordination. Darvish has a tall 6-foot-5, 225-pound frame, whereas Tanaka is built more along the lines of Yovani Gallardo or Kyle Lohse at 6-foot-2, 205 pounds.

Tanaka wraps his wrist in the back of his arm action, but that doesn’t seem to hamper his command. One of the differences between the two pitchers is that, while Darvish stands tall in his delivery, Tanaka’s drop-and-drive mechanics result in his fastball coming in without the same downhill angle, which is why some scouts think fastball is more hittable than the pure velocity might otherwise indicate.

“The fastball’s coming in on a flatter plane,” said a second American League scout, “and that’s why it’s hard for him to create a good angle naturally. The split works well for him for that purpose, because if he didn’t have a splitter that went down, that fastball would get absolutely crushed. And obviously the slider helps take the heat off the fastball, too. But if you’re sitting on a fastball that’s going in at 96, it might go out at 106.”

Advantage: DARVISH

FINAL VERDICT

Over the last two seasons, according to Baseball-Reference.com, just six pitchers—Clayton Kershaw, Sale, Justin Verlander, Cliff Lee, Scherzer and Felix Hernandez—have accumulated more Wins Above Replacement (WAR) than Darvish. Nobody has more strikeouts in that stretch than Darvish, who has outstanding stuff, solid control and thrown around 200 innings per season in his major league career. He is a true ace.

Tanaka projects more as a No. 2, a frontline starter, but he’s a different pitcher from Darvish. That’s certainly not a knock on Tanaka—compare nearly anyone to Darvish, Verlander, Kershaw or Jose Fernandez and they won’t stack up well either. Tanaka should be one of the best pitchers in the major leagues this season, and there are some scouts who do prefer Tanaka to Darvish.

But in evaluating both pitchers at the time they left Japan, Darvish comes out ahead.